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Nonsense problem

bjagflyer

New member
<DIV>A train is travelling due south at 120 mph.</DIV>
<DIV></DIV>
<DIV>A fly is flying due north along the same stretch of track at 5mph.</DIV>
<DIV></DIV>
<DIV>The fly strikes the front of the train square-on, and sticks there.</DIV>
<DIV></DIV>
<DIV>Because the fly has changed direction, now on a reciprocal course to that which it was originally flying, it must have completely stopped at some time during its directional transition.</DIV>
<DIV></DIV>
<DIV>If the fly was momentarily stationary at thetime at which it changed direction,so must the train have been...............</DIV>
<DIV></DIV>
<DIV>Answers on a five pound note please, to..........</DIV>
 
The fly has instantly changed a forward speed of 5 mph in a reverse speed of 120 mph. If it would have managed to hit the breaks, stop and reverse throttle it wouldn't be sticking to the windshield as it is now.


If you promise to do the same exercise like the fly I'll send you a 5 pound note
smiley36.gif



Alex


PS : Or do you prefer flowers ? ...


PS2 : Now if the fly was travelling at 99.9 % of light speed, would its mass have been sufficient to stop the train ?
 
If the fly was momentarily stationary at thetime at which it changed direction,so must the train have been...............


Due to the pliable nature of the flys body, only parts of it would be stationary. There would be a moment when it's head would have been moving south with the train while it's rear would have been continuing to move north.
 
So does this boil down to a centre of gravity problem or and this is just a wild guess...


Is there some mystery force at work that will ultimately allow the fly to crush his enemy (the train)...


Or maybe its like in that ultra realistic bio-pic (Charlie's Angles)where if you jump in the air, kick your legs out wide, time starts to dialate...


Theories are for the weak, guesswork is your only friend


Kev
 
Bertrand Russell used a train analogy to help explain the theory of relativity, but his analogy involved firing a gun from the middle of the train. The thing is, I understood what he was saying.


I'm not so sure about this fly analogy. Maybe you could have a third party write a book about it, but I think Bertrand Russell's dead.
smiley1.gif
 

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